﻿#region LicenseHeader

// Copyright 2012 The Trustees of Indiana University.  All rights reserved.
// 
// The Indiana University licenses this file to you under the Apache License, 
// Version 2.0 (the "License"); you may not use this file except in compliance 
// with the License.  You may obtain a copy of the License at 
// 
// http://www.apache.org/licenses/LICENSE-2.0
// 
// Unless required by applicable law or agreed to in writing, software 
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
//  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  
// See the License for the specific language governing permissions and 
// limitations under the License.
// 
// @author Thilina Gunarathne (tgunarat@indiana.edu)

#endregion

#region

using System;

#endregion

namespace AzureMRCore.DataTypes
{
    /**
     * Used to store a whole matrix as a value.
     */

    public class MatrixValue<TYPE> : IValue
    {
        public TYPE[][] Matrix { get; set; }
        public Int32 BlockHeight { get; set; }
        public Int32 Width { get; set; }
        // RowBlock block number
        public Int32 RowBlock { get; set; }
        // actualy row offset
        public Int32 RowOffset { get; set; }

        #region IValue Members

        public string GetTextValue()
        {
            throw new NotImplementedException();
        }

        public bool ParseValue(object value)
        {
            if (value is TYPE[][])
            {
                Matrix = (TYPE[][]) value;
                return true;
            }
            return false;
        }

        public byte[] GetBytes()
        {
            if (typeof (TYPE) != typeof (double))
            {
                throw new NotImplementedException();
            }

            byte[] bytes = new byte[Width*BlockHeight*8 + 16];
            Buffer.BlockCopy(BitConverter.GetBytes(BlockHeight), 0, bytes, 0, 4);
            Buffer.BlockCopy(BitConverter.GetBytes(Width), 0, bytes, 4, 4);
            Buffer.BlockCopy(BitConverter.GetBytes(RowBlock), 0, bytes, 8, 4);
            Buffer.BlockCopy(BitConverter.GetBytes(RowOffset), 0, bytes, 12, 4);
            for (int j = 0; j < BlockHeight; j++)
            {
                Buffer.BlockCopy(Matrix[j], 0, bytes, (j*Width*8) + 16, Width*8);
            }
            return bytes;
        }

        public bool FromBytes(byte[] value)
        {
            if (typeof (TYPE) != typeof (double))
            {
                throw new NotImplementedException();
            }

            BlockHeight = BitConverter.ToInt32(value, 0);
            Width = BitConverter.ToInt32(value, 4);
            RowBlock = BitConverter.ToInt32(value, 8);
            RowOffset = BitConverter.ToInt32(value, 12);

            Matrix = new TYPE[BlockHeight][];
            for (int j = 0; j < BlockHeight; j++)
            {
                Matrix[j] = new TYPE[Width];
                Buffer.BlockCopy(value, (j*Width*8) + 16, Matrix[j], 0, Width*8);
            }
            return true;
        }

        public long Size()
        {
            return BlockHeight*Width*8;
        }

        #endregion

        public static MatrixValue<TYPE> GetInstance(TYPE[][] matrix, Int32 height, Int32 width, Int32 row,
                                                    Int32 rowOffset)
        {
            var instance = new MatrixValue<TYPE>
                {
                    Matrix = matrix,
                    BlockHeight = height,
                    Width = width,
                    RowBlock = row,
                    RowOffset = rowOffset
                };
            return instance;
        }
    }
}